Gall-inducers
Guides
Aphalaridae
jumping plant lice, psyllids, lerp insects
Aphalaridae is a family of sap-sucking insects in the superfamily Psylloidea, commonly known as jumping plant lice or psyllids. The family contains approximately 749 species with worldwide distribution except Antarctica. Members are small, phloem-feeding insects, often highly host-specific. The family was revised in 2012 and 2021 to include seven subfamilies based on molecular and morphological data. Several species are significant agricultural and forestry pests, including the red gum lerp psyllid (Glycaspis brimblecombei) and the common pistachio psyllid (Agonoscena pistaciae).
Eriococcidae
Felt Scales, Eriococcids, Bark Scales
Eriococcidae is a family of scale insects in the order Hemiptera, commonly known as felt scales or eriococcids. As of 2023, the family comprises 109 genera and 681 species. Members are phloem-feeding herbivores typically associated with specific plant hosts. The family is not monophyletic; recent ribosomal DNA research indicates it represents an aggregation of several distinct evolutionary lineages, with morphologically similar species sometimes being distantly related. Many species produce distinctive waxy ovisacs or induce galls on host plants.
Momphidae
mompha moths
Momphidae is a cosmopolitan family of microlepidopteran moths comprising approximately 115-120 described species. Adults are small, with wingspans up to 21 mm, and narrow forewings often bearing raised scale tufts. The family exhibits remarkable ecological diversity, with larvae occupying six distinct hostplant tissue types: leaves, flowers, fruits, stems, roots, and shoot tips. Phylogenetic studies have identified six major clades corresponding to distinct feeding modes including leaf mining, gall induction, and stem or seed boring. Many species are host-plant specialists, particularly on Onagraceae.
Nematinae
nematine sawflies
Nematinae is a large subfamily of sawflies (Hymenoptera: Tenthredinidae) comprising over 1,250 described species across approximately 40 genera. The subfamily exhibits a reversed latitudinal diversity gradient, with species richness peaking in boreal forest zones rather than tropical regions, likely associated with the abundance of willow (Salix) hosts. Nematinae display diverse feeding strategies including external leaf feeding, leaf mining, and gall induction, with larvae utilizing over 20 plant families.
Nichollsiella
Nichollsiella is a genus of oak cynipid gall wasps described in 2021 from the Nearctic region. The genus comprises three species: N. arizonica, N. sulcata, and N. puigi. As members of the tribe Cynipini, these wasps induce galls on oak trees. The genus was established during a broader taxonomic revision that reorganized several previously described species into new genera based on morphological and molecular data.
Piceacecis
Piceacecis is a genus of gall midges (Diptera: Cecidomyiidae) described by Gagné in 2014. The genus is associated with spruce trees (genus Picea), as indicated by its etymology. As a recently described genus within the diverse gall midge family, its species are likely specialized in inducing galls on spruce foliage or shoots. The genus has been recorded from Denmark.